No effect of garlic extract supplement on serum lipid levels in hypercholesterolemic subjects

Objective: The authors assessed the effects of an enteric-coated Thai garlic extract tablet standardized for allicin-releasing potential on serum lipid levels in hypercholesterolemic subjects. Subjects and Method: The authors performed a randomized, double-blind, placebo-controlled trial in 136 hypercholesterolemic subjects (cholesterol concentrations ≥ 5.2 mmol/L; mean age ± SD: 47.0 ± 6.6 yr). All subjects were given dietary advice to lower fat intake within 4 weeks and were advised to eat normally during the study period. The subjects were randomly assigned to receive an enteric-coated Thai garlic extract tablet once daily (standardized to 1.12% allicin or 5.6 mg/tablet), or placebo after the evening meal for 12 weeks. Seventy subjects (32.9% male; mean age ± SD and BMI of 47.0 ± 6.6 yr and 24.6 ± 3.3 kg/m²) received the garlic extract treatment while 66 subjects (37.9% male, mean age ± SD and BMI of 47.0 ± 6.0 yr and 24.3 ± 3.4 kg/m²) received placebo. Results: There were no statistically significant changes in serum total cholesterol, triglycerides, low-density lipoprotein (LDL) cholesterol and high-density lipoprotein (HDL) cholesterol after the 12-week treatment as analyzed on repeated measures by analysis of variance. In addition, no changes in plasma glucose, liver and renal functions were found. Conclusions: Treatment with an enteric garlic-coated Thai garlic extract and dietary advice did not produce any significant changes in lipid levels in subjects with hypercholesterolemia.